Sanding apparatus

ABSTRACT

A sanding apparatus is disclosed that includes a multi-panel thin-wall cabinet in the interior of which is formed a dustsettling chamber and the sides of which provide supporting structure for at least one enclosed sander assembly. An air passage is formed between the dust-settling chamber and the sander assembly so that exhaust air coupled to the dust-settling chamber will draw the sanding dust from the sander assembly into the settling chamber.

limited States Patent 1 Solheim Sept. 25, 1973 SANDING APPARATUS [76]Inventor: Karsten Solheim, 10412 North 37th St., Phoenix, Ariz. 85028 22Filed: Nov. 18, 1971 211 App]. No.: 200,005

[52] US. Cl 51/148, 51/273, 144/252 R [51] Int. Cl B24b 21/04, B24b55/06 [58] Field of Search 51/135 R, 135 BT, 51/137, 148, 270, 271,273,170 EB; 144/252 R [56] References Cited UNITED STATES PATENTS1,062,248 5/1913 Mueller 51/273 1,621,931 3/1927 Johnson 51/135 R2,449,519 9/1948 Sutton 51/148 2,565,510 10/1951 Martin 51/273 2,640,3046/1953 McEwan.... 51/148 3,049,842 10/1962 Murschel 51/273 3,110,98911/1963 Dawsonetal. SI/135 OTHER PUBLICATIONS Hammond of Kalamazoo,catalog number 75, page 8, model number 50 ed.

Primary ExaminerDonald G. Kelly Assistant Examiner-Howard N. GoldbergAttorney-Herbert E. Haynes, Jr.

[57] ABSTRACT A sanding apparatus is disclosed that includes amultipanel thin-wall cabinet in the interior of which is formed adust-settling chamber and the sides of which provide supportingstructure for at least one enclosed sander assembly. An air passage isformed between the dust-settling chamber and the sander assembly so thatexhaust air coupled to the dust-settling chamber will draw the sandingdust from the sander assembly into the settling chamber.

22 Claims, 13 Drawing Figures PATENTEDSEPZSIQH I 3,760,538

SHEEI 1 0? a I N VE N'TOR. 102 164257. SbU/E/M AGENT PATENIEUSEPZS I973sum 2 or a mm T n T 2 m WM M PATENTEU 3.760.538

SHEU l 0F 4 INVENTOR. 1642505 SOAA/E/M A GENT BACKGROUND OF THEINVENTION 1. Field of the Invention This invention relates to sandingapparatus and more particularly to a sanding mechanism having anintegral dust settling chamber.

2. Description of the Prior Art Heavy duty or industrial type sandingequipment normally includes a belt-sander, a dust-settling device, anair filter mechanism and a source of negative air pressure. Theseinstallations are designed so that sanding dust is removed from the beltsander and routed through vacuum ducts to the remotely locateddustsettling device. All but very fine particles of the sanding dust arecollected within the settling device, with the remaining dust particlesbeing removed by routing the exhaust from the settling device tosuitable air filtering mechanisms.

In general, prior art belt sanders are fabricated with heavy bases uponwhich beam type super structures are provided for supporting the wheels,belt and associated drive mechanisms. Some of the prior art belt sandersmake little or no provisions for enclosing the belt or removing thesanding dust from the proximity of the machine or its operator. However,in more sophisticated installations, belt guards, either cast or formedof sheet matal are provided for safety purposes and may incorporatevacuum duct work for removing the sanding dust and routing it to aremotely located dust settling device.

One particular prior art belt sander is formed with a pedestal type baseenclosure having a belt guard assembly extending angularly upwardlytherefrom. Both the base and the belt guard are formed of heavycastings. This apparatus is driven by an electric motor positioned onthe base and extending into the base enclosure to power a drive wheel.An endless sanding beltpasses over the drive wheel and over a contactwheel rotatably journalled in the uppermost end of the belt guard. Anaccess opening is formed in the belt guard adjacent to the contact wheelto permit application of a workpiece to the belt. A remote vacuum sourceis connected to the base enclosure so that air will flow into theapparatus through the access opening, and will pass down through thebelt guard and out of the base enclosure to a remote dust-settlingdevice.

When metallic workpieces are being sanded, particular problems resultfrom the metallic dust particles which short out the drive motors andother electric devices such as switches, circuit breakers and the like.In the particular prior art sander hereinbefore described, as well asother similar prior art sanders, this problem is particularly acute dueto the electric equipment being mounted adjacent to the base which isnecessary to maintain a low center of gravity and thus provide arelatively stable machine.

These prior art belt sanders are, by the nature of their design, bulkyand heavy machines which qre not easily assembled or dismantled. Thesecharacteristics result in time-consuming and costly handlingdifficulties whenever the machines must be shipped, stored or relocated.

Except for very expensive special purpose highly sophisticated sandingmechanisms, the prior art belt sanders are single work station devices.Thus, in manufacturing installations where a plurality of work stationsare needed, it is a common practice to connect a vacuum duct from eachof a plurality of sanders to a common manifold. The manifold is in turnconnected to a remotely located dust-settling device. This arrangementresults in a maze of vacuum ducts and necessitates one or more separatesettling devices.

Therefore, in view of the foregoing, a need exists for i a new anduseful sanding apparatus which eliminates some of the problemsassociated with the prior art sanding mechanisms.

SUMMARY OF THE INVENTION In accordance with the invention, a new anduseful sanding apparatus is disclosed. The sanding apparatus of thepresent invention comprises a multipanel thinwall housing or cabinet,the interior of which forms an integral dust-settling chamber. The sidewalls of the cabinetprovide supporting structure for at least oneenclosed belt sander assembly.

The electric motor and other necessary electric equipment may be locatedeither within the housing above the dust settling chamber or in anisolated compartment below the dust settling chamber.

Exhaust air may be provided by a suitable vacuum motor mounted on thesanding apparatus or may be coupled from a remote source to the dustsettling chamber which is provided with an air passage communicatingwith the enclosed belt sander assembly Thus air flow is directedinwardly into the belt sander assembly through a workpiece accessopening formed therein, through the air passage into the dust settlingchamber.

According, it is one object of the present invention to provide a newand useful sanding apparatus.

Another object of the present invention is to provide a new and usefulsanding apparatus the supporting structure of which is of thin-wallconstruction.

Another object of the present invention is to provide a new and usefulsanding apparatus having a large integrally formed dust settlingchamber.

Another object of the present invention is to provide a new and usefulsanding apparatus in which a thin wall cabinet houses a dust settlingchamber and provides supporting structure for at least one belt sanderassembly.

Another object of the present invention is to provide a new and usefulsanding apparatus upon which a plurality of belt sanding assemblies aremounted on a common support structure having an integral dust settlingchamber formed therein.

Another object of the present invention is to provide a new and usefulsanding apparatus in which the electrical equipment is located in asubstantially dust-free location.

Another object of the present invention is to provide a new and usefulsanding apparatus in which a thin wall cabinet houses a dust settlingchamber and provides supporting structure for at least one sandingassembly and drive means therefor. the sanding apparatus may alsoinclude a filter assembly and vacuum supplying means to form acompletely self-contained apparatus.

Still another object of the present invention is to provide a new anduseful sanding apparatus which may be shipped or stored in flatlight-weight containers and may be easily assembled with a minimumamount of tooling.

The foregoing and other objects of this invention, the various featuresthereof, as well as the invention itself, may be more fully understoodfrom the following description when read in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view of thesanding apparatus of the present invention incorporating the variousfeatures thereof;

FIG. 2 is a fragmentary sectional view taken on the line 2-2 of FIG. 1;

FIG. 3 is an enlarged fragmentary sectional view taken on the line 3-3of FIG. 1;

FIG. 4 is a fragmentary sectional view taken on the line 4-4 of FIG. 3;

FIG. 5 is a fragmentary sectional view taken on the line 5-5 of FIG. 3;

FIG. 6 is a plan view of a modified form of the sanding apparatusillustrated in FIG. 1;

FIG. 7 is a plan view of another modified form of the sanding apparatusillustrated in FIG. 1;

FIG. 8 is a plan view partially broken away to illustrate the featuresof another embodiment of the sander apparatus of the present invention;

FIG. 9 is a side elevation partially broken away of the sander apparatusof the embodiment illustrated in FIG.

FIG. 10 is a fragmentary front elevation taken on the line 10-10 of FIG.9;

FIG. 11 is a fragmentary rear elevation, partially broken away, taken onthe line 11-11 of FIG. 9,

FIG. 12 is an enlarged fragmentary sectional view of the sandingapparatus shown in FIGS. l-7 illustrating a vacuum supplying means andfilter assembly mounted thereon; and

FIG. 13 is an enlarged fragmentary sectional view of the sandingapparatus shown in FIGS. 8-11 illustrating a vacuum supplying means andfilter assembly mounted thereon.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring more particularly tothe drawings, FIG. 1 illustrates one form of a sanding apparatus of thepresent invention which is indicated generally by the reference numeral15. The sanding apparatus 15 has a cabinet 16 to which a plurality ofsander assemblies 17 may be attached.

The cabinet 16 is a multipanel housing which may be fabricated of sheetmetal, or other suitable materials, to form a thin-wall structure. Inthe preferred embodiment of the present invention the cabinet 16 isshown as a six-sided, box-shaped geometric figure having four verticaland two horizontal panels. The inherent structural rigidity of this typeof structure is well known in the art. However, other geometric formsmay be employed to suit particular requirements. Examples of other formsof construction may include a five-panel structure, seven-panelstructure or any multipanel structure.

The cabinet 16 has four spaced apart upstanding rectangular walls 18which are attached to each other to form an endless wall assembly. Eachof the walls 18 are provided with a flange 21 at its lower end so thatthe sanding apparatus 15 may be leveled and attached to a floor surfacein an appropriate manner.

It should be noted that the flanges 21 could be replaced with legs (notshown) or any other suitable support and leveling device.

A substantially horizontal upper shelf 22 is attached at its peripheraledges 23 to the upper ends 24 of the walls 18 such as by sheet metalscrews, bolts or the like.

A substantially horizontally disposed lower shelf 28, best seen in FIGS.1 and 2, is attached at its peripheral edges 29 to the walls 18 in thesame manner as the upper shelf 22.

The area enclosed between the upper shelf 22, the lower shelf 28 and thewalls 18 is defined as a dust settling or collecting chamber 30.

The upper shelf 22 is provided with a suitable coupling flange 34 towhich one end of an air duct 35 is connected. The air duct 35 isconnected at its other end to a remotely located high velocity vacuumdevice (not shown).

Due to the relatively large volumetric area within the chamber 30 ascompared to the cross sectional area of the air duct 35, the highvelocity air movement within the air duct 35 results in a low velocityexhaust air movement through the settling chamber 30. The low velocityair movement through the chamber 30 allows the heavy particles of thesanding dust, which enter therein from the sander assemblies 17 as willbe described, to settle on the lower shelf 28. Thus it may be apparentthat only very fine or light-weight dust particles will be exhaustedfrom the chamber 30. A filter assembly 36 may be provided within thedust settling chamber 30 for filtering the exhaust air as willhereinafter be described in detail. The air and any dust particlesexhausted from the chamber 30 may be routed through additional externalfiltering apparatus (not shown).

As seen in FIGS. 1 and 2, the sanding apparatus 15 is provided with adoor 37 adjacent to the lower shelf 28 to permit access to the settlingchamber 30 so that the settled sanding dust may be periodically removed.

As seen in FIG. 1, four enclosed sander assemblies 17 are provided, eachbeing attached to a different one of the side walls 18 of the cabinet16. The assemblies 17 are identical structures therefore only one willnow be described.

The sander assembly 17 is provided with a housing 40 or enclosing meanshaving a vertically disposed inwardly positioned base wall 41 which ismounted adjacent to and in contiguous contact with the outwardlydisposed surface of the wall 18 and is maintained in this position bybolts or other suitable mounting devices. The housing 40 is providedwith an upper end wall 42, a lower end wall 43, a rear end wall 44 and afront end wall 45. The walls 42-45 are spaced apart with respect to eachother, are normal to the base wall 41 and extend outwardly therefrom toform the housing 40 into a box-shaped structure. Each of the walls 42-45are provided with an inwardly disposed lip 46 formed on their respectiveoutermost extending edges to which a suitable air sealing gasket 47 issecured.

A door 48 is mounted on the housing 40 by a hinge 50 which isappropriately secured to the rear wall 44. The door 48 is suitablyreinforced to provide a rigid structure which sealingly engages thegasket 47 when the door 48 is held in the closed position by a closinghandle 51 (FIG. 1).

An access opening 54 is formed in the housing 40 adjacent to the cornerformed by the junction of the front wall 45 with the lower wall 43. Theopening 54 is formed by eliminating a portion of the lower wall 43 andproviding a notch 55 in the base wall 41 (FIG. 3) and a similar notch 56in the door 48 (FIG. 1). The opening 54 exposes a portion of a sandingmechanism 60, to be hereinafter described, so that a workpiece may beapplied thereto.

The base wall 41 is provided with an exhaust opening 58 which isadjacent to a similar aperture 59 formed in the wall 18 of the cabinet16 thus providing an air passage communicating therethrough. With theaccess opening 54 formed in the housing 40 and the remainder thereofsealed as hereinbefore described, exhaust air movement caused by thevacuum applied to the settling chamber 30 results in an air pathinwardly directed through the access opening 54 and through theapertures 58 and 59 and into the chamber 30.

The sanding mechanism 60 is mounted within the housing 40. The mechanism60 includes a drive wheel 61, an adjustable wheel 62, an idler orcontact wheel 63 and an endless sanding belt 64.

It should be understood that the sanding mechanism 60 may be modified tosuit particular requirements and such modifications could include atwo-wheel or multiwheel arrangement to accommodate shorter or longerbelt lengths.

As seen best in FIGS. 3 and 4, the drive wheel 61 is coupled through anaperture 66 formed in the base wall 41 of the housing 40 to an electricmotor 68 or drive means. The motor 68 is mounted on the upper shelf 22of the cabinet 16. The shelf 22 is provided with a plurality ofelongated inverted hat-shaped in cross section structural braces 69secured to the lower surface thereof. The braces 69 reinforce the uppershelf 22 to form a rigid mounting surface for supporting a plurality ofthe motors 68, a separate motor 68 is provided for each of the sandingassemblies 17.

It should be noted that the motors 68 and the other necessary electricequipment (not shown) mounted on the upper shelf 22 are surrounded bythe upstanding portions of the housings 40, thus locating the electricequipment of the sanding apparatus in a substantially dust-free area.

The endless sanding belt 64 is driven in a counterclockwise direction bythe drive wheel 61, as indicated by an arrow 70 in FIG. 3. The belt 64passes over the adjusting wheel 62 and the contact wheel 63.

The contact wheel 63 is rotatably journaled on a trunion 72 which issuitably mounted on the base wall 41 adjacent to the access opening 54of the housing 40.

The adjusting wheel 62 is rotatably mounted on a trunion 75 carried onan adjusting device 76 which provides means for adjusting belt tensionand tracking path. The adjusting device 76, as best seen in FIGS. 3 and5, includes an L-shaped bracket 77 fixedly secured to the base wall 41of the housing 40 such as by bolts 78. A swing plate 79 is pivotablysuspended by a pivot pin 80 from the bracket 77. The plate 79 is alsosecured to the base wall 41 of the'housing 40 by screws 81 positioned indiagonally opposed corners of the plate 79. The screws 81 are employedto initially longitudinally align the plate 79 and are each providedwith a spring 82 so that the plate 79 may be pivotably moved about thepivot pin 80 by an adjusting knob 83, the threaded shank 84 of whichbears against the plate 79. It should be readily apparent that movementof the knob causes pivotable movement of the plate 79 about the pivotpin 80 which is limited'to a small arcuate movement by the springs 82.However, small movements of the plate 79 are all that is needed toadjust the longitudinal axis of the trunion about which the wheel 62revolves. These small changes in the disposition of the trunions 75permit adjustment of the tracking path of the belt 64 over the wheels61, 62 and 63.

The tension applied to the belt 64 is accomplished by l the sameadjusting device 76. The tensioning is accomplished by an elongated arm86 which carries the trunion 75 on one end thereof and is pivotablyattached on its other end by a pivot pin 87 to the plate 79. Arcuatemovement of the arm 86 and thus the wheel 62 in the direction of anarrow 88 (FIG. 3) applies tension to the belt 64, and movement of thearm 86 and wheel 62 in the opposite direction relieves the tension. Thearm 86 is biased in the tension applying direction by a compressionspring 90. One end of the spring 90 contacts a lower surface of the arm86 and the other end is retained upon a spring keeper 91. The keeper 91is carried on a shank 92 of an adjusting knob 93 which is threadablyadjustable in an L-shaped bracket 94 dependingly attached to the plate79. I

Since the belt 64 moves in the direction of arrow 70 as hereinbeforedescribed, most of the sanding dust will be directed downwardly from theproximity of the contact wheel 63. Only a small portion of the dust willenter the housing 40 by being carried on the belt 64 and by the inflowof air through the openings 54. Therefore a scoop 98 is attached to thecabinet 16 such as by screws. The scoop is provided with an upwardlydisposed opening 100 which directs the dust downwardly and into thesettling chamber 30 through an opening 101 (FIG. 2) formed in the wall18 thereof. The scoop is provided with an inclined surface 102 which isformed into a substantially horizontally disposed bottom 103 adjacent tothe opening 101. The bottom 103 is provided to catch any foreignmaterial which may accidentally drop into the scoop 98.

The hereinbefore described sanding apparatus 15 which is seen best inFIG. 1 is shown as having four individually operable sander assemblies17 mounted thereon to provide four separate work stations. FIG. 6illustrates a sanding apparatus 15a which is provided with two sanderassemblies 17 to form a two-work station apparatus. FIG. 7 illustrates asingle work station sanding apparatus 15b. The cabinets, settlingchambers and sander assemblies of the sanding apparatuses 15a and 15bare fabricated by employing the same basic techniques and operatingmechanisms as previously described for the apparatus 15.

With reference now to FIGS. 8-11 wherein a modified sanding apparatus ofthe present invention is indicated generally by the reference numeral115.

The sanding apparatus is best suited to provide a low profile two-workstation machine which employs the same basic components and constructionmethods as the previously described sanding apparatus 15. It will benoted that some rearranging of components was needed to best meet therequirements of this particular application.

The sanding apparatus 115 has a cabinet 116 which provides supportingstructure for a pair of sander assemblies 117.

The cabinet 1 16 is a multipanel housing fabricated of thin wallmaterials to provide an endless wall assembly having a pair of spacedapart side walls 118, a front panel 119, a rear panel 120, a base panel121 and a top panel 123. An upper shelf 122 and a lower shelf 128 aremounted within the cabinet 116. The upper and lower shelves 122 and 128respectively are spacedly arranged to provide a dust settling chamber130.

A coupling flange 134 is provided in the rear panel 120 to which an airduct 135 is connected. A filter assembly 136 may be provided within thedust settling chamber 130 as will hereinafter be described in detail. Ahigh velocity vacuum device (not shown) is coupled to the settlingchamber 130 which causes it to function in the same manner as thehereinbefore described settling chamber 30. A clean-out door 137 isprovided for removing sanding dust from the settling chamber 130.

As best seen in FIG. 8, a pair of sander assemblies 117 are provided,each being positioned adjacent to a different one of the side walls 118.The sander assemblies 117 are identical to each other, therefore onlyone will now be described.

It will become apparent from the description to follow that somestructural differences exist between the apparatus and the apparatus115. It should be noted that these differences are merely designexpedients as both of the sanding apparatuses 15 and 115 could befabricated by employing either structural technique.

The cabinet 116 is provided with a cavity 140 or enclosing means formedtherein which is laterally disposed with respect to the dust settlingchamber 130, and is separated therefrom by the wall 118 which serves asa divider panel. Therefore, it may be seen that the cavity 140 servesthe same purpose in the apparatus 115 as housing 40 does in theapparatus 15.

The wall or divider panel 118 is recessed so that the front panel 119and the rear panel 120 extend beyond the wall 118 to provide a rearextending end 144 and a front extending end 145 which form the front andrear enclosing structure for the cavity 140. The base panel 121 enclosesthe bottom of the cabinet 116 and extends beyond the divider panel 118to form an extending end 143 for enclosing the bottom of cavity 140. Thetop panel 123 is positioned to enclose the top of the cabinet 116 andprovide an extending end 142 for enclosing the top of the cavity 140.The top panel 123 is provided with an access lid 149.

A suitably reinforced door 148 is mounted on a hinge 150 to sealinglyenclose the cavity 140 in the manner hereinbefore described for door 48of the housing 40.

As best seen in FIGS. 8 and 11, the base panel 121 and top panel 123extend across the entire width of the sanding apparatus 115. Thus, alower isolated electric equipment compartment 152 is formed below thesettling chamber 130, and an upper isolated electric equipmentcompartment 153 is provided above the settling chamber 130. The upperand lower compartments 152 and 153 are at ambient pressure so thatmigration of the sanding dust from the negatively pressurized sandingassemblies 117 and settling chamber 130 will not occur due to thepressure differential.

An access opening 154 is provided in the upper end of the frontextending end 145 to expose a portion of a sanding mechanism 160, tohereinafter be described in detail, so that a workpiece may be appliedthereto.

The wall or divider panel 118 is provided with at least one aperture orexhaust opening 158 formed therein which provides an air passage thatcommunicates between the cavity 140 and the settling chamber 130. Theexhaust air path through the apparatus 115 will therefore be inwardlythrough the access opening 154 into the cavity and through the aperture158 into the settling chamber 130.

The sanding mechanism 160 is similar to the previously described sandingmechanism 60, and includes a drive wheel 161, an adjustable wheel 162, acontact wheel 163 and an endless sanding belt 164.

As shown in FIG. 11, the drive wheel 161 is driven by a double endedelectric motor 168 or other suitable drive means located in the isolatedcompartment 152 below the settling chamber 130. It should be noted thatthe motor 168 could have been mounted within the upper compartment 153without affecting the stability of the apparatus 115 due to the inherentstructural rigidity of the cabinet 116.

The adjustable wheel 162 is carried on an adjusting device 176 which maybe identical to the previously described adjusting device 76, and willtherefore not be described again.

The contact wheel 163 is mounted externally of the cabinet 116 on ahat-shaped in cross section brace 171 appropriately secured to the frontof the cabinet. The brace 171 carries a trunion mount assembly 172 uponwhich the contact wheel 163 is rotatably journaled.

The belt 164 is driven in the direction of an arrow (FIG. 9) thereforedirecting the sanding dust downwardly into a scoop 98 located below thecontact wheel 163.

The brace 171 is provided with laterally extending shield portions 173to protect an operator from any sanding dust which may be carriedoutwardly by the belt 164. A centrally located portion of the brace 171between the trunion mounts 172 may be employed to mount a stop-startswitch 174 or other control devices as desired.

Other electric devices and wiring (not shown) may be mounted in eitherthe upper or lower compartments 152 and 153.

A modified mounting assembly 199 upon which the apparatus 115 may besecured to the floor is shown in FIG. 11.

With reference now to FIGS. 12 and 13 wherein the sanding apparatuses 15and 115 are each shown with a vacuum supplying means 200 and 230respectively to illustrate these apparatuses as self-contained units.

FIG. 12 shows the coupling flange 34 formed in the upper shelf 22 of thesanding apparatus 15 as having the vacuum supplying means 200 mountedthereon. The vacuum supplying means 200 is shown as a centrifugal blowerhaving an outlet 202 to which an external filter bag 204 is secured suchas by a clamp 206. If further filtering of the exhaust air is desired,an exhaust duct (not shown) could be connected to the outlet 202 forrouting the exhaust to remote filtering devices (not shown). Otherwise,the exhaust may be either expelled directly into the atmosphere orthrough the external filter bag 204 as shown.

As hereinbefore briefly described, the filter assembly 36 may beinternally mounted within the dust settling chamber 30 of the sandingapparatus 15. It should be noted that the filter assembly 36 may beprovided regardless of whether the source of vacuum is derived from aremotely located device (not shown) or is provided by the vacuumsupplying means 200.

The filter assembly 36 includes a support frame 208 which is suitablyattached to the lower surface of the upper shelf 22 and is adjacent tothe coupling flange 34 so as to circumscribe the inlet thereto. Thesupport frame 208 has a mounting flange 210 from which a grill 212depends. The grill 212 is shown as a wire mesh structure but could befabricated in any suitable manner so as to provide support for a filterbag 2M and to hold the bag 214 in the open position against the flow ofthe exhaust air.

FIG. 13 illustrates the coupling flange 134 formed in the back panel 120of the sanding apparatus 115 as having the vacuum supplying means 230mounted thereon. The vacuum supplying means 230 is shown as acentrifugal blower having an outlet 232 to which an external filter bag234 may be attached.

The vacuum supplying means 230 could be mounted within the isolatedchamber 153 so that the outlet 232 would extend through the backpanel120 of the cabinet 116.

As previously mentioned the sanding apparatus 115 could be provided witha filter assembly 136. The filter.

assembly 136 is constructed similar to the filter assembly 36, aspreviously described, and is provided with a support frame 236 uponwhich a suitable filter bag 238 is mounted.

The filter assemblies 36 and 136 may be provided with suitable shakerdevices (not shown) for periodically removing the sanding dust whichwould tend to collect on the surface of the filter bags 2114 and 238.

While the principles of the invention have now been made clear in thepreferred embodiment, there will be immediately obvious to those skilledin the art many modifications of structure, arrangement, proportions,the elements, materials and components, used in the practice of theinvention, and otherwise, which are particularly adapted for specificenvironments and operating requirements without departing from thoseprinciples. The appended claims are therefore intended to cover andembrace any such modifications within the limits only of the true spiritand scope of the invention.

What I claim is: i

l. A sanding apparatus comprising:

a. a free standing thin-wall cabinet having a dust settling chamberformed therein, said cabinet having a first and a second aperture formedin one side thereof which open into the dust settling chamber;

b. coupling means on said cabinet for connecting a source of exhaust airto the dust settling chamber thereof;

c. an enclosed sander assembly supportingly mounted on the one side ofsaid cabinet and positioned laterally adjacent to the settling chamberthereof, said sander assembly having an exhaust opening formed thereinwhich aligns with and is in contiguous engagement with the firstaperture of said cabinet for exhausting sanding dust from the interiorof said sender assembly, and having an access opening formed therein forpermitting application of a workpiece thereto, the access openingpositioned above the second aperture of said cabinet;

d. a scoop mounted on the one side of said cabinet below the accessopening of said sander assembly for catching sanding dust droppingtherefrom, said scoop communicating with the second aperture of saidcabinet for directing the sanding dust into the settling chamberthereof; and

e. drive means mounted on said cabinet in an area isolated from the dustsettling chamber and coupled to drive said enclosed sander assembly.

2. A sanding apparatus as claimed in claim 1 wherein said multipanelthin-wall cabinet comprises:

a. a plurality of side walls attached to each other to form an endlesswall assembly;

b. an upper shelf attached at its peripheral edges to each of said sidewalls; and

c. a lower shelf attached at its peripheral edges to each of said sidewalls, said upper and lower shelves and said side walls spaced apart toenclose the dust settling chamber therebetween.

3. A sanding apparatus as claimed in claim 1 wherein said coupling meansis located at a position remote from the bottom of the dust settlingchamber.

4. A sanding apparatus as claimed in claim 1 wherein said enclosedsander assembly comprises:

a. enclosing means in which the access opening and the exhaust openingare formed;

b. an endless sandingbelt movably mounted within said enclosing means;

c. a drive wheel supportingly positioned within said enclosing means bysaid drive means and coupled to be rotatably driven thereby;

d. an adjusting device mounted within said enclosing means and having anadjusting wheel rotatably journaled thereon over which said sanding beltpasses, said adjusting device being adjustable to control the trackingpath and tension of said sanding belt; and

e. a contact wheel journaled for rotation adjacent to the access openingformed in said enclosing means, said contact wheel positioned forengagement with said sanding belt.

5. A sanding apparatus as claimed in claim 1 further comprising a vacuumsupplying means supportingly carried on said cabinet by said couplingmeans for supplying the exhaust air to the dust settling chamber.

6. A sanding apparatus as claimed in claim 1 further comprising a filterassembly mounted within the dust settling chamber of said cabinet andpositioned adjacent to said coupling means for filtering the exhaustair.

7. A sanding apparatus as claimed in claim 1 further comprising:

a. a vacuum supplying means mounted on said coupling means for supplyingthe exhaust air to the dust settling chamber; and

b. a filter assembly mounted within the dust settling chamber of saidcabinet and positioned to circumscribe the inlet to said coupling meansfor filtering the exhaust air drawn into said vacuum supplying meansthrough said coupling means.

8. A sanding apparatus comprising:

a. an endless wall assembly formed of a plurality of thin-wall panels,said endless wall assembly forming the side enclosures for a dustsettling chamber, said endless wall assembly having at least oneaperture formed in one of the thin-wall panels thereof and opening intothe dust settling chamber;

b. a thin-wall upper shelf attached at its peripheral edges to each ofthe panels of said endless wall assembly for closing the top of the dustsettling chamber;

c. a thin-wall lower shelf attached at its peripheral edges to each ofthe panels of said endless wall assembly for closing the bottom of thedust settling chamber;

d. coupling means formed on said upper shelf for coupling a source ofexhaust air to the dust settling chamber;

e. a housing supportingly mounted on said endless wall assembly andextending above said upper shelf, said housing having an access openingand an exhaust aperture formed therein, the exhaust aperture positionedto align with and in contiguous engagement with the aperture formed inthe one thinwall panel of said endless wall assembly;

f. a sanding mechanism mounted within said housing;

and

g. drive means mounted on the upper surface of said upper shelf andhaving a shaft extending into said housing for driving said sandingmechanism.

9. A sanding apparatus as claimed in claim 8 wherein said housing isdemountably attached to said endless wall assembly.

10. A sanding apparatus as claimed in claim 8 further comprising a scoopmounted on said endless wall assembly and positioned adjacent to theaccess opening formed in said housing, said scoop communicating with thedust settling chamber through an opening formed in said endless wallassembly.

11. A sanding apparatus as claimed in claim 8 wherein said housingcomprises:

a. a base wall removably mounted on the exterior of said endless wallassembly;

b. a plurality of extending walls each normal to said base wall andpositioned on a different peripheral edge thereof, at least one of saidextending walls having an access opening formed therein to permitapplication of a workpiece to said sanding mechanism; and

c. a door mounted on one of said extending walls and adapted to enclosesaid housing.

12. A sanding apparatus as claimed in claim 8 wherein said sandingmechanism comprises:

a. an endless sanding belt;

b. a drive wheel supportingly positioned within said housing androtatably driven by the shaft of said drive means, said drive wheeldrivingly engaging said sanding belt;

0. a contact wheel rotatably journaled within said housing adjacent tothe access opening thereof, said contact wheel positioned to engage saidsanding belt; and

d. an adjustable device mounted within said housing for supporting arotatable adjusting wheel over which said sanding belt passes, saiddevice adjustable for positioning the adjusting wheel to control thetracking path and tension of said sanding belt.

13. A sander apparatus as claimed in claim 8 wherein said endless wallassembly is formed of four panels each of which is adapted to providesupporting structure for one of said housings, each of said housingscommunicating with the dust settling chamber and having a sandermechanism mounted therein.

14. A sanding apparatus as claimed in claim 8 further comprising avacuum supply means mounted on said coupling means for providing theexhaust air coupled to the dust settling chamber by said coupling means.

15. A sanding apparatus as claimed in claim 8 further comprising afilter assembly mounted on the lower surface of said upper shelf anddepending therefrom into the dust settling chamber, said filter assemblymounted adjacent to said coupling means and positioned to circumscribethe inlet thereto.

16. A sanding apparatus comprising:

a. a multipanel thin-wall cabinet having a dust settling chamber formedtherein and at least one enclosed cavity laterally disposed with respectto the dust settling chamber and separated therefrom by a divider panelwhich has at least one aperture formed therein, said cabinet having anaccess opening formed therein which communicates between the exterior ofsaid cabinet and the enclosed cavity;

b. coupling means on said cabinet for coupling exhaust air to the dustsettling chamber thereof;

c. a sander mechanism mounted within the enclosed cavity of saidcabinet; and

(1. drive means mounted in said cabinet and isolated from the dustsettling chamber said drive means coupled through the divider panel todrive said sander mechanism.

17. A sanding apparatus as claimed in claim 16 wherein said multipanelthin-wall cabinet comprises:

a. a base panel;

b. a front panel attached to said base;

c. a rear panel attached to said base and spaced from said rear panel;

(1. a top panel attached to the upper ends of said front and said rearpanels;

e. a pair of side panels at least one of which is recessed to form thedivider panel and to provide extending ends on each of said base, front,rear and top panels, at least one of the extending ends having theaccess opening formed therein;

f. a door mounted on one of the extending ends for closing the cavityformed in said cabinet; and

g. at least one shelf mounted within the dust settling chamber to forman isolated compartment in which said drive means is mounted.

18. A sander apparatus as claimed in claim 16 wherein said sandermechanism comprises:

a. an endless sanding belt;

b. a drive wheel supportingly positioned adjacent to the divider paneland adapted to be driven by said drive means;

0. a contact wheel rotatably journaled adjacent to the access openingformed in said cabinet and positioned to engage said sanding belt; and

d. an adjusting device mounted on the divider panel for supportinglycarrying an adjusting wheel over which said sanding belt passes, saiddevice adjustable for positioning the adjusting wheel to determine thetracking path and tension of said sanding belt.

19. A sander apparatus as claimed in claim 16 wherein said apparatusfurther includes:

a. a scoop formed on said cabinet adjacent to the access opening formedtherein, said scoop adapted to catch sanding dust and direct it into theenclosed cavity formed in said cabinet; and

b. means on said cabinet for emptying settled sanding dust from theinterior of the dust settling chamber.

20. A sander apparatus as claimed in claim 16 wherein said cabinet isprovided with an upper isolated chamber vertically disposed above thedust settling chamber and with a lower isolated chamber verticallydisposed below. the dust settling chamber.

21. A sander apparatus as claimed in claim 16 wherein said multipanelthin-wall cabinet comprises a four-sided structure having a pair ofopposed enclosed cavities formed therein each of which communicates M b.a frame mounted within the dust settling chamber of said cabinet andpositioned adjacent to said coupling means; and c. a filter bag mountedon said frame for filtering out sanding dust in the exhaust air drawnfrom the dust settling chamber by said vacuum supplying means.

2. A sanding apparatus as claimed in claim 1 wherein said multipanelthin-wall cabinet comprises: a. a plurality of side walls attached toeach other to form an endless wall assembly; b. an upper shelf attachedat its peripheral edges to each of said side walls; and c. a lower shelfattached at its peripheral edges to each of said side walls, said upperand lower shelves and said side walls spaced apart to enclose the dustsettling chamber therebetween.
 3. A sanding apparatus as claimed inclaim 1 wherein said coupling means is located at a position remote fromthe bottom of the dust settling chamber.
 4. A sanding apparatus asclaimed in claim 1 wherein said enclosed sander assembly comprises: a.enclosing means in which the access opening and the exhaust opening areformed; b. an endless sanding belt movably mounted within said enclosingmeans; c. a drive wheel supportingly positioned within said enclosingmeans by said drive meaNs and coupled to be rotatably driven thereby; d.an adjusting device mounted within said enclosing means and having anadjusting wheel rotatably journaled thereon over which said sanding beltpasses, said adjusting device being adjustable to control the trackingpath and tension of said sanding belt; and e. a contact wheel journaledfor rotation adjacent to the access opening formed in said enclosingmeans, said contact wheel positioned for engagement with said sandingbelt.
 5. A sanding apparatus as claimed in claim 1 further comprising avacuum supplying means supportingly carried on said cabinet by saidcoupling means for supplying the exhaust air to the dust settlingchamber.
 6. A sanding apparatus as claimed in claim 1 further comprisinga filter assembly mounted within the dust settling chamber of saidcabinet and positioned adjacent to said coupling means for filtering theexhaust air.
 7. A sanding apparatus as claimed in claim 1 furthercomprising: a. a vacuum supplying means mounted on said coupling meansfor supplying the exhaust air to the dust settling chamber; and b. afilter assembly mounted within the dust settling chamber of said cabinetand positioned to circumscribe the inlet to said coupling means forfiltering the exhaust air drawn into said vacuum supplying means throughsaid coupling means.
 8. A sanding apparatus comprising: a. an endlesswall assembly formed of a plurality of thin-wall panels, said endlesswall assembly forming the side enclosures for a dust settling chamber,said endless wall assembly having at least one aperture formed in one ofthe thin-wall panels thereof and opening into the dust settling chamber;b. a thin-wall upper shelf attached at its peripheral edges to each ofthe panels of said endless wall assembly for closing the top of the dustsettling chamber; c. a thin-wall lower shelf attached at its peripheraledges to each of the panels of said endless wall assembly for closingthe bottom of the dust settling chamber; d. coupling means formed onsaid upper shelf for coupling a source of exhaust air to the dustsettling chamber; e. a housing supportingly mounted on said endless wallassembly and extending above said upper shelf, said housing having anaccess opening and an exhaust aperture formed therein, the exhaustaperture positioned to align with and in contiguous engagement with theaperture formed in the one thin-wall panel of said endless wallassembly; f. a sanding mechanism mounted within said housing; and g.drive means mounted on the upper surface of said upper shelf and havinga shaft extending into said housing for driving said sanding mechanism.9. A sanding apparatus as claimed in claim 8 wherein said housing isdemountably attached to said endless wall assembly.
 10. A sandingapparatus as claimed in claim 8 further comprising a scoop mounted onsaid endless wall assembly and positioned adjacent to the access openingformed in said housing, said scoop communicating with the dust settlingchamber through an opening formed in said endless wall assembly.
 11. Asanding apparatus as claimed in claim 8 wherein said housing comprises:a. a base wall removably mounted on the exterior of said endless wallassembly; b. a plurality of extending walls each normal to said basewall and positioned on a different peripheral edge thereof, at least oneof said extending walls having an access opening formed therein topermit application of a workpiece to said sanding mechanism; and c. adoor mounted on one of said extending walls and adapted to enclose saidhousing.
 12. A sanding apparatus as claimed in claim 8 wherein saidsanding mechanism comprises: a. an endless sanding belt; b. a drivewheel supportingly positioned within said housing and rotatably drivenby the shaft of said drive means, said drive wheel drivingly engagingsaid sanding belt; c. a contact wheel rotatably journaled within saidhousing adjacent to tHe access opening thereof, said contact wheelpositioned to engage said sanding belt; and d. an adjustable devicemounted within said housing for supporting a rotatable adjusting wheelover which said sanding belt passes, said device adjustable forpositioning the adjusting wheel to control the tracking path and tensionof said sanding belt.
 13. A sander apparatus as claimed in claim 8wherein said endless wall assembly is formed of four panels each ofwhich is adapted to provide supporting structure for one of saidhousings, each of said housings communicating with the dust settlingchamber and having a sander mechanism mounted therein.
 14. A sandingapparatus as claimed in claim 8 further comprising a vacuum supply meansmounted on said coupling means for providing the exhaust air coupled tothe dust settling chamber by said coupling means.
 15. A sandingapparatus as claimed in claim 8 further comprising a filter assemblymounted on the lower surface of said upper shelf and depending therefrominto the dust settling chamber, said filter assembly mounted adjacent tosaid coupling means and positioned to circumscribe the inlet thereto.16. A sanding apparatus comprising: a. a multipanel thin-wall cabinethaving a dust settling chamber formed therein and at least one enclosedcavity laterally disposed with respect to the dust settling chamber andseparated therefrom by a divider panel which has at least one apertureformed therein, said cabinet having an access opening formed thereinwhich communicates between the exterior of said cabinet and the enclosedcavity; b. coupling means on said cabinet for coupling exhaust air tothe dust settling chamber thereof; c. a sander mechanism mounted withinthe enclosed cavity of said cabinet; and d. drive means mounted in saidcabinet and isolated from the dust settling chamber said drive meanscoupled through the divider panel to drive said sander mechanism.
 17. Asanding apparatus as claimed in claim 16 wherein said multipanelthin-wall cabinet comprises: a. a base panel; b. a front panel attachedto said base; c. a rear panel attached to said base and spaced from saidrear panel; d. a top panel attached to the upper ends of said front andsaid rear panels; e. a pair of side panels at least one of which isrecessed to form the divider panel and to provide extending ends on eachof said base, front, rear and top panels, at least one of the extendingends having the access opening formed therein; f. a door mounted on oneof the extending ends for closing the cavity formed in said cabinet; andg. at least one shelf mounted within the dust settling chamber to forman isolated compartment in which said drive means is mounted.
 18. Asander apparatus as claimed in claim 16 wherein said sander mechanismcomprises: a. an endless sanding belt; b. a drive wheel supportinglypositioned adjacent to the divider panel and adapted to be driven bysaid drive means; c. a contact wheel rotatably journaled adjacent to theaccess opening formed in said cabinet and positioned to engage saidsanding belt; and d. an adjusting device mounted on the divider panelfor supportingly carrying an adjusting wheel over which said sandingbelt passes, said device adjustable for positioning the adjusting wheelto determine the tracking path and tension of said sanding belt.
 19. Asander apparatus as claimed in claim 16 wherein said apparatus furtherincludes: a. a scoop formed on said cabinet adjacent to the accessopening formed therein, said scoop adapted to catch sanding dust anddirect it into the enclosed cavity formed in said cabinet; and b. meanson said cabinet for emptying settled sanding dust from the interior ofthe dust settling chamber.
 20. A sander apparatus as claimed in claim 16wherein said cabinet is provided with an upper isolated chambervertically disposed above the dust settling chamber and with a lowerisolated chamber veRtically disposed below the dust settling chamber.21. A sander apparatus as claimed in claim 16 wherein said multipanelthin-wall cabinet comprises a four-sided structure having a pair ofopposed enclosed cavities formed therein each of which communicates withthe dust settling chamber and each having a sander mechanism mountedtherein.
 22. A sanding apparatus as claimed in claim 16 furthercomprising: a. a vacuum supplying means mounted on said coupling meansfor supplying the exhaust air coupled to the dust settling chamber bysaid coupling means; b. a frame mounted within the dust settling chamberof said cabinet and positioned adjacent to said coupling means; and c. afilter bag mounted on said frame for filtering out sanding dust in theexhaust air drawn from the dust settling chamber by said vacuumsupplying means.